Russia's Defense Ministry says its forces fired four cruise missiles from the Mediterranean Sea to hit Islamic State targets in Syria.

The ministry said the missiles came from a frigate and a submarine and landed near the city of Palmyra, striking heavy weapons and Islamic State militants who had deployed there from the group's de facto capital in Raqqa.

Russia said it notified the United States, Turkey and Israel before firing the missiles. It did not say exactly when the strikes took place.

In this frame grab provided May 31, 2017 by Russian Defense Ministry press service, IS target is hit by long-range Kalibr cruise missile in the area of Palmyra, Syria.

The Palmyra area has seen a lot of fighting during the past year, with control of the city changing between Islamic State fighters and the Syrian government several times. Syrian forces currently hold the city, but clashes continue.

Russian forces have been involved in Syria since late 2015 in support of Syrian President Bashar al-Assad, and Russia has been criticized by the United States and others for not focusing enough of its air campaign against Islamic State targets.